The present invention relates to an optical disc device for recording a signal on an optical disc such as a compact disc or reproducing a recorded signal therefrom, and in particular, to an optical-pickup driving mechanism and an optical-disc loading mechanism.
A conventional optical disc device normally allows an optical disc to be installed on a disc tray that slides out from an opening in the front panel of the device according to a user""s operation, and then withdraws the disc tray with the optical disc to a predetermined position inside the device. Then, the optical disc, which has reached the predetermined position inside the device, is sandwiched between a turn table and a clamper and then rotated at a predetermined rotation speed. An optical pickup reproduces a signal recorded within a predetermined range on the optical disc by moving in response to the track position of the signal.
In the conventional optical disc device, different motors are used as driving sources for driving these operations, that is, the three operations including the disc loading, disc rotating, and optical-pickup feeding operations. That is, the conventional optical disc device is normally configured so as to use three motors in total.
In the conventional optical disc device, however, the motors were among the most expensive parts and there was a problem that the use of the three motors prevented the price of the entire device from being reduced.
The present invention solves this problem, and its object is to reduce the number of motors used in the device in order to provide a more inexpensive optical disc device.
To attain this object, an optical disc device comprises a traverse base including an optical pickup and a feed motor that drives the optical pickup forward and backward from the inner circumferential position of the optical disc to the outer circumferential position thereof, and comprises a loading means for transferring the optical disc from the exterior of the device body onto a traverse base and a loading driving means for driving the loading means using the feed motor that is also used for driving the optical pickup.
In this configuration, the feed motor can move the optical pickup to reproduce a signal and eject the optical disc to the exterior of the device, thereby reducing the number of motors used in the device in order to provide a more inexpensive optical disc device.
The invention is an optical disc device characterized in that a traverse base is disposed on a device body and includes an optical pickup that records a signal on an optical disc or that reproduces a signal recorded thereon and a feed motor that drives via an optical-pickup driving means, the optical pickup forward and backward from the inner circumferential position of the optical disc to the outer circumferential position thereof, and in that the device body comprises a loading means for transferring the optical disc from the exterior of the device body onto the traverse base and a loading driving means for driving the loading means using the feed motor that is also used for driving the optical pickup. This optical disc device uses the feed motor to move the optical pickup and also to drive the loading means, thereby enabling the optical disc to be ejected to the exterior of the device, and eliminates the needs for an optical-disc loading motor that has been required in the conventional optical disc device.
According to an object of the invention the optical pickup can move up to an extended switching position that is closer to the center of the optical disc than a signal position range on the optical disc in which signals are recorded is, and in that when the pickup is at the extended switching position, the rotational driving force of the feed motor is switched and transmitted to the loading driving means. This optical disc device uses the feed motor to move the optical pickup to the signal inner-circumferential-end switching position on the optical disc and further continues rotating the feed motor in the same direction, thereby enabling the loading driving means to automatically eject the optical disc to the exterior of the device.
According to a further object of the invention an inner-circumference detecting is provided for detecting that the optical pickup has moved to the inner-circumferential-end switching position within the signal position range due to the rotational driving force of the feed motor; and a power transmission switching means is provided for rotationally driving the feed motor to further move the pickup toward the inner circumference of the optical disc when the inner circumferential detecting switch executes detection, thereby switching the driving force of the feed motor to the loading driving means, whereby the rotating direction of the feed motor is switched according to a detection signal from the inner-circumference detecting switch in order to selectively switch the transmission of the rotational driving force of the feed motor between the driving of the loading means and the driving of the optical pickup. This optical disc device detects that the optical pickup is at the inner-circumferential-end switching position or has moved thereto while the inner-circumference detecting switch is being turned off, and allows the optical pickup to further move toward the inner circumference of the optical disc even after it has turned on the inner-circumference detecting switch.
According to yet another objection of the invention, the traverse base includes a turn table on which the optical disc is placed, said traverse base being mounted to be able to swing around its rear end, and wherein the device further comprises an elevating means for swinging the traverse base to elevate and lower the turn table relative to the optical disc and a power transmission means for transmitting the driving force of the feed motor to the elevating means in response to an optical-disc transfer operation performed by the loading means, whereby the turn table is elevated and lowered in response to the optical-disc transfer operation in order that the optical disc can be installed on and removed from the turn table. After the elevating means has elevated the traverse base, the turn table or the like can clamp the optical disc almost in the horizontal direction. After the traverse base has been lowered by using the driving force of the feed motor via the power transmission means to activate the elevating means, the turn table can be moved downward while being inclined to unclamp the optical disc so that the optical disc can pass over the turn table when it is installed from the exterior of the device and when it is removed from the interior.
The loading driving means includes driving gears that transmit the rotational driving force of the feed motor and a rack that is provided in part of the loading means and meshes with the driving gear, the rack teeth of the rack having a tooth trace angle almost the same as the rotational-movement angle of the traverse base. When the turn table, that is, the traverse base rotationally moves in such a way that its front is inclined downward, the driving gear is also inclined relative to the horizontal state. Since the rack teeth of the rack are configured to incline so as to have a tooth trace angle almost the same as the swing angle of the traverse base, the driving gear and the rack constantly mesh with each other correctly.